What happened
On March 18, 2023, at 14:33 UTC, a JOUAV CW-100 unmanned aerial vehicle (UAV), registration AR-VNT-798, crashed at La Plata Airport in the Buenos Aires province. The flight was part of a technical demonstration and equipment delivery process for the Ministry of Security of the Province of Buenos Aires, conducted by the manufacturer.
The aircraft successfully took off and transitioned from multirotor to fixed-wing mode, operating within a pre-defined safety corridor. However, during the final phase of the flight, as the aircraft began an automated vertical descent to 30 meters, it experienced significant instability. This instability was caused by an anomalous response from the front right motor, which led to a total loss of control and the subsequent destruction of the aircraft upon impact with the ground.
The investigation
Investigators examined flight data and video footage to reconstruct the final moments of the flight. The analysis focused on the telemetry of the Pulse Width Modulation (PWM) signals sent from the flight controller to the Electronic Speed Control (ESC) units. The data revealed that while the flight controller continued to send appropriate commands to the other rotors, the front right motor received multiple high-speed signals without a corresponding functional output.
The investigation also reviewed the electrical architecture of the UAV, noting that the aircraft utilized two batteries per motor. While the flight logs did not show a failure in the primary power system or the flight controller's command emission, the investigation considered the possibility of an intermittent signal interruption within the battery connectors of the affected motor.
Findings
- The primary cause of the accident was a failure in the front right motor during the descent phase.
- The flight controller maintained correct command signals (PWM) to the motors, indicating the software and command logic were functioning as intended.
- An intermittent electrical disconnection or signal loss at the battery connectors for the front right motor is a suspected contributing factor.
- Although not related to the crash, the investigation identified that the pilot in command did not hold a valid license recognized under Argentine regulations for this specific operation.